mirror/freebsd
1
0
Fork 0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-16 10:20:30 +00:00
Code Issues Releases Activity
a5a492981c
freebsd/lib/libkvm/kvm_getswapinfo.c

590 lines
12 KiB
C
Raw Blame History

/*
* Copyright (c) 1999, Matthew Dillon. All Rights Reserved.
* Copyright (c) 2001, Thomas Moestl
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided under the terms of the BSD
* Copyright as found in /usr/src/COPYRIGHT in the FreeBSD source tree.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/conf.h>
#include <sys/blist.h>
#include <sys/sysctl.h>
#include <vm/vm_param.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <kvm.h>
#include <nlist.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>
#include "kvm_private.h"
static struct nlist kvm_swap_nl[] = {
{ "_swapblist" }, /* new radix swap list */
{ "_swdevt" }, /* list of swap devices and sizes */
{ "_nswdev" }, /* number of swap devices */
{ "_dmmax" }, /* maximum size of a swap block */
{ "" }
};
#define NL_SWAPBLIST 0
#define NL_SWDEVT 1
#define NL_NSWDEV 2
#define NL_DMMAX 3
static int kvm_swap_nl_cached = 0;
static int nswdev;
static int unswdev; /* number of found swap dev's */
static int dmmax;
static void getswapinfo_radix(kvm_t *kd, struct kvm_swap *swap_ary,
int swap_max, int flags);
static int kvm_getswapinfo2(kvm_t *kd, struct kvm_swap *swap_ary,
int swap_max, int flags);
static int kvm_getswapinfo_kvm(kvm_t *, struct kvm_swap *, int, int);
static int kvm_getswapinfo_sysctl(kvm_t *, struct kvm_swap *, int, int);
static int nlist_init(kvm_t *);
static int getsysctl(kvm_t *, char *, void *, size_t);
#define SVAR(var) __STRING(var) /* to force expansion */
#define KGET(idx, var) \
KGET1(idx, &var, sizeof(var), SVAR(var))
#define KGET1(idx, p, s, msg) \
KGET2(kvm_swap_nl[idx].n_value, p, s, msg)
#define KGET2(addr, p, s, msg) \
if (kvm_read(kd, (u_long)(addr), p, s) != s) \
warnx("cannot read %s: %s", msg, kvm_geterr(kd))
#define KGETN(idx, var) \
KGET1N(idx, &var, sizeof(var), SVAR(var))
#define KGET1N(idx, p, s, msg) \
KGET2N(kvm_swap_nl[idx].n_value, p, s, msg)
#define KGET2N(addr, p, s, msg) \
((kvm_read(kd, (u_long)(addr), p, s) == s) ? 1 : 0)
#define KGETRET(addr, p, s, msg) \
if (kvm_read(kd, (u_long)(addr), p, s) != s) { \
warnx("cannot read %s: %s", msg, kvm_geterr(kd)); \
return (0); \
}
#define GETSWDEVNAME(dev, str, flags) \
if (dev == NODEV) { \
strlcpy(str, "[NFS swap]", sizeof(str)); \
} else { \
snprintf( \
str, sizeof(str),"%s%s", \
((flags & SWIF_DEV_PREFIX) ? _PATH_DEV : ""), \
devname(dev, S_IFCHR) \
); \
}
int
kvm_getswapinfo(
kvm_t *kd,
struct kvm_swap *swap_ary,
int swap_max,
int flags
) {
int rv;
#ifdef DEBUG_SWAPINFO
int i;
#endif
/*
* clear cache
*/
if (kd == NULL) {
kvm_swap_nl_cached = 0;
return(0);
}
rv = kvm_getswapinfo2(kd, swap_ary, swap_max, flags);
/* This is only called when the tree shall be dumped. It needs kvm. */
if (flags & SWIF_DUMP_TREE) {
#ifdef DEBUG_SWAPINFO
/*
* sanity check: Sizes must be equal - used field must be
* 0 after this. Fill it with total-used before, where
* getswapinfo_radix will subtrat total-used.
* This will of course only work if there is no swap activity
* while we are working, so this code is normally not active.
*/
for (i = 0; i < unswdev; i++) {
swap_ary[i].ksw_used = swap_ary[i].ksw_total -
swap_ary[i].ksw_used;
}
#endif
getswapinfo_radix(kd, swap_ary, swap_max, flags);
#ifdef DEBUG_SWAPINFO
for (i = 0; i < unswdev; i++) {
if (swap_ary[i].ksw_used != 0) {
fprintf(stderr, "kvm_getswapinfo: swap size "
"mismatch (%d blocks)!\n",
swap_ary[i].ksw_used
);
}
}
/* This is fast enough now, so just do it again. */
rv = kvm_getswapinfo2(kd, swap_ary, swap_max, flags);
#endif
}
return rv;
}
static int
kvm_getswapinfo2(
kvm_t *kd,
struct kvm_swap *swap_ary,
int swap_max,
int flags
) {
if (ISALIVE(kd)) {
return kvm_getswapinfo_sysctl(kd, swap_ary, swap_max, flags);
} else {
return kvm_getswapinfo_kvm(kd, swap_ary, swap_max, flags);
}
}
int
kvm_getswapinfo_kvm(
kvm_t *kd,
struct kvm_swap *swap_ary,
int swap_max,
int flags
) {
int ti = 0;
/*
* namelist
*/
if (!nlist_init(kd))
return (-1);
{
struct swdevt *sw;
int i;
ti = unswdev;
if (ti >= swap_max)
ti = swap_max - 1;
if (ti >= 0)
bzero(swap_ary, sizeof(struct kvm_swap) * (ti + 1));
KGET(NL_SWDEVT, sw);
for (i = 0; i < unswdev; ++i) {
struct swdevt swinfo;
int ttl;
KGET2(&sw[i], &swinfo, sizeof(swinfo), "swinfo");
/*
* old style: everything in DEV_BSIZE'd chunks,
* convert to pages.
*
* new style: swinfo in DEV_BSIZE'd chunks but dmmax
* in pages.
*
* The first dmmax is never allocating to avoid
* trashing the disklabels
*/
ttl = swinfo.sw_nblks - dmmax;
if (ttl == 0)
continue;
if (i < ti) {
swap_ary[i].ksw_total = ttl;
swap_ary[i].ksw_used = swinfo.sw_used;
swap_ary[i].ksw_flags = swinfo.sw_flags;
GETSWDEVNAME(swinfo.sw_dev,
swap_ary[i].ksw_devname, flags
);
}
if (ti >= 0) {
swap_ary[ti].ksw_total += ttl;
swap_ary[ti].ksw_used += swinfo.sw_used;
}
}
}
return(ti);
}
/*
* scanradix() - support routine for radix scanner
*/
#define TABME tab, tab, ""
static int
scanradix(
blmeta_t *scan,
daddr_t blk,
daddr_t radix,
daddr_t skip,
daddr_t count,
kvm_t *kd,
int dmmax,
int nswdev,
struct kvm_swap *swap_ary,
int swap_max,
int tab,
int flags
) {
blmeta_t meta;
#ifdef DEBUG_SWAPINFO
int ti = (unswdev >= swap_max) ? swap_max - 1 : unswdev;
#endif
KGET2(scan, &meta, sizeof(meta), "blmeta_t");
/*
* Terminator
*/
if (meta.bm_bighint == (daddr_t)-1) {
if (flags & SWIF_DUMP_TREE) {
printf("%*.*s(0x%06x,%d) Terminator\n",
TABME,
blk,
radix
);
}
return(-1);
}
if (radix == BLIST_BMAP_RADIX) {
/*
* Leaf bitmap
*/
#ifdef DEBUG_SWAPINFO
int i;
#endif
if (flags & SWIF_DUMP_TREE) {
printf("%*.*s(0x%06x,%d) Bitmap %08x big=%d\n",
TABME,
blk,
radix,
(int)meta.u.bmu_bitmap,
meta.bm_bighint
);
}
#ifdef DEBUG_SWAPINFO
/*
* If not all allocated, count.
*/
if (meta.u.bmu_bitmap != 0) {
for (i = 0; i < BLIST_BMAP_RADIX && i < count; ++i) {
/*
* A 0 bit means allocated
*/
if ((meta.u.bmu_bitmap & (1 << i))) {
int t = 0;
if (nswdev)
t = (blk + i) / dmmax % nswdev;
if (t < ti)
--swap_ary[t].ksw_used;
if (ti >= 0)
--swap_ary[ti].ksw_used;
}
}
}
#endif
} else if (meta.u.bmu_avail == radix) {
/*
* Meta node if all free
*/
if (flags & SWIF_DUMP_TREE) {
printf("%*.*s(0x%06x,%d) Submap ALL-FREE {\n",
TABME,
blk,
radix
);
}
#ifdef DEBUG_SWAPINFO
/*
* Note: both dmmax and radix are powers of 2. However, dmmax
* may be larger then radix so use a smaller increment if
* necessary.
*/
{
int t;
int tinc = dmmax;
while (tinc > radix)
tinc >>= 1;
for (t = blk; t < blk + radix; t += tinc) {
int u = (nswdev) ? (t / dmmax % nswdev) : 0;
if (u < ti)
swap_ary[u].ksw_used -= tinc;
if (ti >= 0)
swap_ary[ti].ksw_used -= tinc;
}
}
#endif
} else if (meta.u.bmu_avail == 0) {
/*
* Meta node if all used
*/
if (flags & SWIF_DUMP_TREE) {
printf("%*.*s(0x%06x,%d) Submap ALL-ALLOCATED\n",
TABME,
blk,
radix
);
}
} else {
/*
* Meta node if not all free
*/
int i;
int next_skip;
if (flags & SWIF_DUMP_TREE) {
printf("%*.*s(0x%06x,%d) Submap avail=%d big=%d {\n",
TABME,
blk,
radix,
(int)meta.u.bmu_avail,
meta.bm_bighint
);
}
radix >>= BLIST_META_RADIX_SHIFT;
next_skip = skip >> BLIST_META_RADIX_SHIFT;
for (i = 1; i <= skip; i += next_skip) {
int r;
daddr_t vcount = (count > radix) ? radix : count;
r = scanradix(
&scan[i],
blk,
radix,
next_skip - 1,
vcount,
kd,
dmmax,
nswdev,
swap_ary,
swap_max,
tab + 4,
flags
);
if (r < 0)
break;
blk += radix;
}
if (flags & SWIF_DUMP_TREE) {
printf("%*.*s}\n", TABME);
}
}
return(0);
}
static void
getswapinfo_radix(kvm_t *kd, struct kvm_swap *swap_ary, int swap_max, int flags)
{
struct blist *swapblist = NULL;
struct blist blcopy = { 0 };
if (!nlist_init(kd)) {
fprintf(stderr, "radix tree: nlist_init failed!\n");
return;
}
KGET(NL_SWAPBLIST, swapblist);
if (swapblist == NULL) {
if (flags & SWIF_DUMP_TREE)
printf("radix tree: NULL - no swap in system\n");
return;
}
KGET2(swapblist, &blcopy, sizeof(blcopy), "*swapblist");
if (flags & SWIF_DUMP_TREE) {
printf("radix tree: %d/%d/%d blocks, %dK wired\n",
blcopy.bl_free,
blcopy.bl_blocks,
blcopy.bl_radix,
(int)((blcopy.bl_rootblks * sizeof(blmeta_t) + 1023)/
1024)
);
}
scanradix(
blcopy.bl_root,
0,
blcopy.bl_radix,
blcopy.bl_skip,
blcopy.bl_rootblks,
kd,
dmmax,
nswdev,
swap_ary,
swap_max,
0,
flags
);
}
#define GETSYSCTL(kd, name, var) \
getsysctl(kd, name, &(var), sizeof(var))
/* The maximum MIB length for vm.swap_info and an additional device number */
#define SWI_MAXMIB 3
int
kvm_getswapinfo_sysctl(
kvm_t *kd,
struct kvm_swap *swap_ary,
int swap_max,
int flags
) {
int ti, ttl;
size_t mibi, len;
int soid[SWI_MAXMIB];
struct xswdev xsd;
struct kvm_swap tot;
if (!GETSYSCTL(kd, "vm.dmmax", dmmax))
return -1;
mibi = SWI_MAXMIB - 1;
if (sysctlnametomib("vm.swap_info", soid, &mibi) == -1) {
_kvm_err(kd, kd->program, "sysctlnametomib failed: %s",
strerror(errno));
return -1;
}
bzero(&tot, sizeof(tot));
for (unswdev = 0;; unswdev++) {
soid[mibi] = unswdev;
len = sizeof(xsd);
if (sysctl(soid, mibi + 1, &xsd, &len, NULL, 0) == -1) {
if (errno == ENOENT)
break;
_kvm_err(kd, kd->program, "cannot read sysctl: %s.",
strerror(errno));
return -1;
}
if (len != sizeof(xsd)) {
_kvm_err(kd, kd->program, "struct xswdev has unexpected "
"size; kernel and libkvm out of sync?");
return -1;
}
if (xsd.xsw_version != XSWDEV_VERSION) {
_kvm_err(kd, kd->program, "struct xswdev version "
"mismatch; kernel and libkvm out of sync?");
return -1;
}
ttl = xsd.xsw_nblks - dmmax;
if (unswdev < swap_max - 1) {
bzero(&swap_ary[unswdev], sizeof(swap_ary[unswdev]));
swap_ary[unswdev].ksw_total = ttl;
swap_ary[unswdev].ksw_used = xsd.xsw_used;
swap_ary[unswdev].ksw_flags = xsd.xsw_flags;
GETSWDEVNAME(xsd.xsw_dev, swap_ary[unswdev].ksw_devname,
flags);
}
tot.ksw_total += ttl;
tot.ksw_used += xsd.xsw_used;
}
ti = unswdev;
if (ti >= swap_max)
ti = swap_max - 1;
if (ti >= 0)
swap_ary[ti] = tot;
return(ti);
}
static int
nlist_init (
kvm_t *kd
) {
struct swdevt *sw;
if (kvm_swap_nl_cached)
return (1);
if (kvm_nlist(kd, kvm_swap_nl) < 0)
return (0);
/*
* required entries
*/
if (
kvm_swap_nl[NL_SWDEVT].n_value == 0 ||
kvm_swap_nl[NL_NSWDEV].n_value == 0 ||
kvm_swap_nl[NL_DMMAX].n_value == 0 ||
kvm_swap_nl[NL_SWAPBLIST].n_type == 0
) {
return (0);
}
/*
* get globals, type of swap
*/
KGET(NL_NSWDEV, nswdev);
KGET(NL_DMMAX, dmmax);
/*
* figure out how many actual swap devices are enabled
*/
KGET(NL_SWDEVT, sw);
for (unswdev = nswdev - 1; unswdev >= 0; --unswdev) {
struct swdevt swinfo;
KGET2(&sw[unswdev], &swinfo, sizeof(swinfo), "swinfo");
if (swinfo.sw_nblks)
break;
}
++unswdev;
kvm_swap_nl_cached = 1;
return (1);
}
static int
getsysctl (
kvm_t *kd,
char *name,
void *ptr,
size_t len
) {
size_t nlen = len;
if (sysctlbyname(name, ptr, &nlen, NULL, 0) == -1) {
_kvm_err(kd, kd->program, "cannot read sysctl %s:%s", name,
strerror(errno));
return (0);
}
if (nlen != len) {
_kvm_err(kd, kd->program, "sysctl %s has unexpected size", name);
return (0);
}
return (1);
}
Reference in New Issue View Git Blame Copy Permalink